This invention relates to reader apparatus for the reading of documents such as tab cards and badges, such documents having a thickness within a relatively wide range, and in particular reader apparatus adaptable to efficiently transport for reading documents within such a wide range of thicknesses.
In the field of document reading devices, there is an increasing need for readers designed to efficiently process different types of documents, e.g., conventional tab cards, badges, and the like. In the electronic data processing industry, there is a proliferation of systems customized to meet particular needs of data gathering and processing, wherein a large number of one-at-a-time type readers are utilized. Such systems are, for instance, particularly adaptable to large industrial operations where there is a need to plug in a large number of occasionally used data sources at different locations. Frequently, in these systems, the data is encoded on a badge which is worn or carried by a person, which badge is periodically inserted into the reader either for recording of data or for recording of an event. At the same time, it is desirable that the system be able to accommodate other types of documents, such as conventional tab cards. A tab card has a thickness within a range of 0.006 to 0.009 inch, and is typically 0.007 inch in thickness. By contrast, both type 3 and type 5 badges, which find wide acceptance in present day EDP systems, have a thickness within a range of 0.018 to 0.030 inch. Further, badges which include embossing can have a total thickness of up to about 0.048 inch. It is thus seen that a single system may require reader devices capable of accommodating data 20 documents having thickness within a range of about 0.006 to 0.048 . Heretofore, readers have been designed with great precision to accommodate a document of only a predetermined thickness. The requirement to be automatically adaptable to receive documents of different thicknesses creates a great need for a reliable and efficient reader device, without which the system capability is severely limited.